I combined this data with browser share data from StatCounter. Countries are ordered by ARPU.

The gray area is the average revenue per mobile-cellular subscription

The blue line is the linear trend line for iOS browser share

The green line is the linear trend line for Android browser share

Click the picture to see a larger view – Special thanks to @asymco for suggesting a scatter-plot visualization

iOS Browser Share Roughly Tracks Carrier ARPU — Click for larger size

I find this very illuminative. If we assume ARPU is a good proxy for subsidization, then this strongly supports the idea that the iPhone is highly competitive1 versus Android in subsidized markets (the left side), but is simply too expensive in non-subsidized markets (the right side).

The right side of this chart is the visual case for a low-cost iPhone.

In fact, the iPhone mostly wins on the left; the trend line is dragged down by the right ↩